Perception and Acoustics of Vowel Nasality in Brazilian Portuguese

This study explores the relationship between identification, degree of nasality and vowel quality in oral, nasal and nasalized vowels in Brazilian Portuguese. Despite common belief that the language possesses contrastive nasal vowels, literature examination shows that nasal vowels may be followed by a nasal resonance, while nasalized vowels must be followed by a nasal consonant. It is argued that the nasal resonance may be the remains of a consonant that nasalizes the vowel, making nasal vowels simply coarticulatorily nasalized (e.g. [1]). If so, vowel nasality should not be more informative for the perception of a word containing a nasal vowel than for a word containing a nasalized vowel, as nasality is attributed to coarticulation. To test this hypothesis, randomized stimuli containing the first syllable of words with oral, nasal and nasalized vowels were presented to BP listeners who had to identify the stimuli original word. Preliminary results demonstrate that accuracy decreased for nasal and nasalized stimuli. A comparison between patterns of response to measured degrees of vowel acoustic nasality and formant values demonstrate that vowel quality differences may play a more relevant role in word identification than type of nasality in a vowel.